The invention relates to an agitation flotation cell for the preparation of minerals and coals having a vertical agitation shaft with a circular disk at the bottom at right angles to the shaft. The shaft and lower end thereof is particularly used in a floatation cell such as that shown in German Pat. No. 1,164,946, or U.S. Pat. No. 3,256,987, Isenhardt et al, which are incorporated by reference herein in their entirety. In such an arrangement, the upper side of the disk is exposed to a connection with an air intake pipe.
With this construction of the agitator, sludge is sucked up mixed with air and centrifuged off in an outward direction. The direction of the sludge airstream at the circumference of the disk is constantly altered because of the inclined position during rotation. Because of this construction, good turbulence or swirling motion of the air and sludge in the cell takes place.
Inasmuch as the swirling motion of the air and sludge in the cell is dependent upon the inclination of the disk, this may be predetermined in accordance with the cell design and need not be altered. Newer space flotation cells require agitators for a disk with relatively large diameters and require substantial structural heights of the agitator.
In order to lower the structural height of the agitator and attain a better turbulence than with agitator flotation cells heretofore available, the present invention employs radial vanes with disk sections therebetween at angles to each other and to a plane at right angles to the agitator shaft. In a preferred embodiment, two lateral sections which join at a peak to form a roof-shaped upwardly facing surface at one side of the shaft with two similar sections at the other side of the shaft. With the construction as shown and described in accordance with the invention when used with large flotation cells, a substantial increase in degree of efficiency is attained. With small flotation cells, the structural height of the agitator is lowered. A further advantage of the invention is that the uniquely shaped disk is provided, at least on the upper surface with radial vanes or ribs which extend upwardly from the upper planar surface of the disk. With this construction and the decrease of the structural height of the agitator, an improvement in the turbulence of air and sludge is attained in the cell.
It is accordingly an object of the present invention to provide an agitator flotation cell of improved construction which operates with increased efficiency and effectiveness and which further reduces the vertical dimensions necessary.